An electronic device such as a mobile terminal device, a computer, and a television device includes a display device having a display panel such as a liquid crystal panel. Examples of the mobile terminal device include a mobile phone, a smart phone, and PDA. In such a device, a “parallax barrier” function may be used to display stereoscopic images. The parallax barrier function uses the characteristics of human eyes to perceive three-dimensional images based on binocular parallax, that is, difference between the images viewed through the left and right eyes.
Patent Document 1 discloses a display device having a function to display a stereoscopic image. The display device includes a display panel and a parallax barrier attached to each other with adhesive and bonded to each other so as to overlap an image displaying area of the display panel in a plan view.